I did a full interior and exterior minus clay or wax and I charged $130. It took about 3 hrs to do a nice job inside and out on a 99 Villager. Leather detail on 3 rows of seats, dash, carpet and mats were really dirty. This van hadn't been washed, in what seemed like months. Lots of wheel dust buildup, dry leather, dirty carpet. Just nasty.
My customer was very happy with it, and had no issue paying $130. Charge what your work is worth. Call around and see what other people are charging. As the customer on what they want to spend on a cleaning before you do a job.
Doing good work gets you good word of mouth. Doing bad does just the opposite.